﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ExampleClass
{
    class Rectangle{
        int width;
        int height;
        public Rectangle(){
            width=5;
            height=5;
        }
        public Rectangle(int a, int b){
            width=a;
            height=b;
        }
        public int area(){
            return (width*height);
        }
    }
    class Program
    {
        static void Main(string[] args)
        {
            Rectangle recta = new Rectangle(3,4);
            Rectangle rectb = new Rectangle();
            Console.WriteLine("recta:{0}",recta.area());
            Console.WriteLine("rectb:{0}",rectb.area());

        }
    }
}
